标签：ios   swift   apple   

1.1What is Swift

1.2Reference books&&website

https://itunes.apple.com/us/book/swift-programming-language/id881256329?mt=11

https://itunes.apple.com/us/course/developing-ios-8-apps-swift/id961180099

https://itunes.apple.com/cn/course/ios-development-in-swift/id950659946

1.3Variable (var) or Constant (let)

What declared with var is considered mutable while let is immutable.

var myVariable = 42
myVariable = 50
let myConstant = 42
____________________________

let implicitInteger = 70
let implicitDouble = 70.0
let explicitDouble: Double = 70
____________________________

let label = "The width is"
let width = 94
let widthLabel = label + String(width)
____________________________

let apples  = 3
let oranges = 5
let appleSummary = "I have \(apples) apples."    //\() is a way to include values in strings
let fruitSummary = "I have \(apples+oranges) pieces of fruit."

1.4arrys and dictionaries

Create arrays and dictionaries using brackets([]), and access their elements by writing the index or key in brackets.

var shoppingList = ["apple", "banana", "water"]
shoppingList[1] = "a piece of banana"

var occupations = [
    "Jason": "Captain",
    "Kaylee": "Mechanic",
]
occupations["Jayne"] = "Public Relations"
________________________

let emptyArray= [String]()
let emptyDictionary= [String: Flocat]()
________________________
shopplingList= []
occupations= [:]
________________________
import Foundation
var arrayAny: [AnyObject] = []
arrayAny += [1, "Two", false]
arrayAny.append(4.0)
________________________

1.5Loop

Conditionals: if , switch

loops:for-in, for, while

let individualScore = [75, 43, 103, 87, 12]
var teamScore = 0
for score in individualScore {
    if(score > 50) {
       teamScore += 3
    } else {
       teamScore += 1
    }
} 
println(teamScore)
teamScore  //This is a simple way to see the value of a variable inside a playgroud.
_____________________________

var optionalString: String? = "Hello"

optionalString ==nil

var optionalName: String? = "Jason Wang"
var greeting = "Hello!"
if let name = optionalName {
    greeting = "Hello, \(name)"
}
_____________________________

var results: [int] = [] //same as var result: Array[Int]
for i: Int in 0..<100 {
    if i % 7 == 0 {
        results.append(i)
    }
}
results
_____________________________
func color(thing: String?) -> String? {
     if let someThing  = thing {
         switch someThing {
             case let x where x.hasPrefix("green"):
                  return "green"
             case "apple":
                  return "red"
             case "pineapple","banana":
                  return "yellow"
             default:
                  return "unknow"
         }
     } else {
         return nil
     }
}
color("apple")
color("green apple")
color("banana")
color("someThing")
color(nil)

1.6Funcation

func location(city: String) -> (Double, Double) {
    var list = [
        "Shanghai" : (12.233, 15.332),
        "Beijing" : (33.222, 31.333)
    ]
    return list[city] ?? (0, 0)
} 
location("Shanghai")
location("Wuhan")

1.7Closure

var odds = [1, 3, 5, 7].map({number in 3*number})
odds

import Foundation
var array: [UInt32] = []
for _ in 0..<10 {
    array.append(arc4random_uniform(UInt32(100)))
}
array
sort(&array){ $0 < $1 }
array

IOS8 开发之Swift - 自学之路(第一天)

标签：ios   swift   apple   

原文地址：http://blog.csdn.net/jason_wang1989/article/details/43482701